as looking your load 50,70sq. mm cable is not much enough if you are optimising total load than current will be approx. 400amp since your supply voltage is 220v3-ph.
so main cable you need 300sq. mm aluminium as incomming and then distributo via distribution box to all four machines your 40HP load machines need 70Sq. mm aluminium and 25HP Machine need 35sq.mm Aluminium Cable
conductor dia. increase b'caouse of your 220v 3-phase power